Cause and Effect
by ColieMacKenzie
Summary: He holds on to her, fingers entwined, his grip almost bruising but he can't let go. Episode reaction to 5x05, 'Probable Cause.'


**Cause and Effect**

**AN:** Episode reaction to 5x05, "Probable Cause."

* * *

It's like a tidal wave.

Washing over him ferociously, sweeping through his blood, claiming him in desperate surges. He holds on to her, fingers entwined, his grip almost bruising but he can't let go, needs her closer, can't get her close enough, it's never close enough with her.

He watches her, unable to close his eyes; sees the pleasure spread through her, flushing her face, arching her body up against his, a frantic, aching rise and he clings to her, bodies entwined, slick and needy, can't let her go, ever, ever.

And when she breaks he falls with her, grips her tightly through the crush of their shudders, her scent her breaths her sweat like a balm to the frayed edges of his discombobulated thoughts.

* * *

He can't close his eyes. The loft creaks, the wind whips around the corners of his building and his heart thunders, every sound an ominous threat.

He trips his fingers over the slope of Kate's spine, trying to find respite in the calming rhythm, the familiar lines of her shape. Her skin is warm, her body sleep-heavy as she lies draped over his chest. Her hair tumbles over her shoulders in messy waves, her breaths are deep and even with the weighty respite of sleep.

He bands his arm across her lower back, holding her to him and she murmurs indistinctive sounds, snuggles her cheek over his breastbone before she sinks deeper once more.

He stares at his ceiling, and his heart won't stop hammering against his ribcage, in his throat. He sucks in a breath, tries to relax, dismiss the spiral of thoughts that hold him hostage but they circle his mind in a wide, destructive path, over and over and over.

Sleep won't come.

His mind takes inventory as he mentally walks through his loft, looks into every corner, every nook, considers every closet, wondering, worrying. Where all has Tyson been? Did he leaf through his book collection? Touch his clothes? Open his refrigerator? Has it really only been Alexis drinking his orange juice?

Did Tyson rummage through his secret desk drawer that's really not so much secret as it's personal, where he keeps treasured keepsakes, Alexis' popsicle stickman she made in kindergarten, the movie stubs from Forbidden Planet, pages ripped from notebooks with scribbled story ideas, old photos and post-its that Kate has left him, inconsequential to anybody but him.

He was in his home. His _home_. He'd always felt safe here, the security seemingly insurmountable yet Tyson was able to simply walk in. Able to watch them, his family, the people he loves. He could've hurt any of them, and there was nothing, _nothing_ he could've done about it. He grits his teeth, the wave of helplessness rushing back and he tastes blood on his tongue.

How long had he been watching them? Oh god he'd seen them making love.

Nausea climbs his throat, the sense of violation cloying, angering, frightening. He's tainted everything that's beautiful, everything he treasures. He fights it, his brain battling with the thoughts because this man, this _monster_ should not have this power, nobody deserves such power over him but the endless reel keeps playing on in his mind and he sees it everywhere, the evil, taunting grin, the glint of his cold eyes, hears the grate of his voice. Hears it with each crack of his floorboards, each drip of the faucet.

He's still out there, Castle _knows _he's still out there, lying in wait for his next victims, wherever or whoever they might be. He whirls his head around, searches outside the window, eyes flicking along the walls; stares at the slit where the bathroom door is opened. Did they leave that door open?

Is Tyson still watching?

He clenches his arm tighter around Kate, wraps his legs around her too, folding her into a firm embrace, keeping her safe and close and with him. This amazingly beautiful woman, passionate and indomitable. So vulnerable and slight in his arms. Can he even keep her safe?

He'll have to get professionals in here, immediately. Sweep the place for bugs or cameras or whatever might still be hidden. Clean it all too, disinfect everything. Get an extra security system, whatever is top of the line right now.

Tyson made it personal. Violated his home, his safety, his emotional stability and there is anger in him, such grating anger, and anger he understands, he'd expected anger but this overwhelming insecurity, this latent fear feels new and he doesn't know how to shake it off, how to push it deep down, ignore it.

He believed he'd seen it all; they'd gone through so much together, beaten the odds, survived, and he thought himself strong, able to write it out or talk it through, sweep it aside with laughter and jokes, capable of being there for Kate when she needed support or his shoulder to lean on.

And, maybe for the first time, he can truly feel, not just imagine but _sense_ deep-down what Kate must have been experiencing for years, this constant underlying threat to her life, the worry, the taint slicked across every day, never knowing when they might come after you, when everything you've worked for, everything you treasure and everything you are might end, just like that.

_I'll never be safe._

Castle drags her closer, can't help the sob that flies from his mouth, his fingers wrapped around her sides as he crushes her to his chest. She murmurs sleepily, eyelids fluttering. He tries to get himself under control, slow the thunder of his heart, the choppy gulps of his breathing, running his fingers over her back in soothing patterns but her eyes open as she slowly climbs to awareness.

"You okay?" Kate lifts her head to him, her voice scratchy from sleep, palm pressed over his heart.

"Yeah." His voice is no more than a croak but he tries to push it down deep, doesn't want to weigh her down too; he can carry this burden for the both of them.

She plays her fingertips over his skin in nonsensical doodles. "You've been quiet all night."

"Just thinking."

"Your heart is racing." Her eyes blink open wider, adapting to the dark of the night. She rubs her palm over his chest in soothing caresses. "This about Tyson?"

He nods.

"It's over Castle. You killed him." Her reassurances are quiet, calm and maybe she even believes it but he knows it's not true. Knows he'll spend the rest of his life looking over his shoulder.

They both will, until they put those things to rest, once and for all.

"How do you do it?" He wonders, not for the first time but he's never asked before, always just assumed he knew the answer.

She sighs, resting her forehead on his chin for a moment. "I know it sounds trivial, but one day at a time." Kate runs her hands higher, a warm path over his collarbones, his shoulders before she wraps a palm around the back of his neck, looking at him in the dark. Her eyes are luminous, shine with the glint of moonlight sneaking through the blinds.

"Castle, it's taken me too long a time to learn this but you take every day like it's a gift, and you _live_ it. You _don't_ let them _win_."

And he hears it in her voice, so intense, so full, sees and understands, more clearly than ever. How she lives now, has taken control over her destiny, has chosen to live, chosen him. Chosen to be happy, like he asked her to once, chosen to be free. With him. She's with him, and she trusts him with her life, with her heart.

He runs his fingers through her hair, over her cheek and she tilts her cheek into his touch, so familiar and trusting and he needs to ask, can't let it go; he _has_ to make sure again. "You know I'd never do this, right?"

She blinks, the skin between her eyebrows scrunched as she thinks, tries to catch up with the jump of his thoughts before understanding spreads across her features. "Of course. Castle we talked about this. I never doubted you."

"I know. I know you know I didn't do this but I need you to know I never _would_. I would _never_ do this to you; I'd never cheat on you Kate. Never."

She nods, staring at him quietly but then she detangles one of her hands, running her fingers down over the side of his face in a caress so tender that it almost aches.

"I know. I trust you."

She slips her lips over his mouth, kisses him softly and then he cradles her head into the crook of his neck, wrapping his arms securely around her. It bursts from his heart, uncensored, the words almost sobbed, filled with never-ending longing. "You're the best thing that's ever happened to me. I don't want to be alone again. I don't ever want to be without you. I can't lose you."

"You won't," she promises, her voice whispering across the skin of his neck while she finds his hands, laces their fingers together. "You won't lose me."

And even though he knows, they _both _know how it may not stay true, how circumstances beyond their control may rip them apart forever, he hears it for the promise she makes him, and it's enough.

Enough to live.


End file.
